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A forensic worker lifts a a body at a crime scene, in San Juan, Puerto Rico, Thursday, Jan. 11, 2018 . As the island struggles to recover from Hurricane Maria, it is facing one of the biggest spikes in violent crime in nearly a decade amid a widespread power outage, severe unemployment and an increase in police absences.

One of Puerto Rico's deadliest months in recent years has closed, with 78 killings reported in January as the U.S. territory struggles with a surge in violent crime and growing discontent among thousands of police officers.

The killings included a 20-year-old woman found kneeling and burned to death inside a car in the upscale city of Guaynabo and a triple homicide reported in the eastern mountain town of San Lorenzo.

Puerto Rico's homicide rate is roughly 20 killings per 100,000 residents, compared with 3.7 per 100,000 residents on the U.S. mainland.

The majority of people killed last month were young men shot to death. The central mountain town of Caguas reported the highest number of homicides at 18, followed by the capital of San Juan with 14.

Police have issued warrants or arrested suspects in only a handful of the cases. On Thursday, authorities asked the public for help in solving the case of the young woman found burned inside the car. Police said they believe she was on her way to pick up a family member the day she was killed.

Hector Pesquera, head of Puerto Rico's newly created Department of Public Safety, has said most of the killings in January were tied to drugs but added that there was "no rhyme or reason" to explain the surge.

In mid-January, local and federal officials announced they would implement a "broken windows" policing campaign to help reduce the number of killings. The plan is to crack down on all types of violations, including traffic infractions and illegal tints on car windows, to help get criminals off the street and prevent bigger crimes.

The increase in killings came weeks after thousands of police officers began calling in sick daily to protest millions of dollars owed in overtime pay following Hurricanes Irma and Maria. Absences have returned to the normal daily average, Pesquera says, but thousands of police officers are still upset about austerity measures, including a sharp reduction in their monthly pensions and an end to being able to cash in unused sick days.

Puerto Rico Rep. Felix Lassalle, president of the commission of public security, is holding public hearings to address those issues.